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Shaping Machine.


tool altogether.    Special clamps 23 hold the tool,  having large

square holes to receive it, and the turning of the set 'screw serves

both to fix tool to clamp and clamp in tool box.

The tool itself is shaped as in Fig. 172, being so bent back as to

place the point nearly in a line with the hinge and prevent ' digging.'
The Shaping Machine is a planer with moving tool and

fixed work, having on this account some  advantage  for  small

articles ; for if a moving
table be employed, its
stroke must exceed the
length of work, so as to
leave space for the ac-
quisition of velocity in
such a heavy mass \
while the moving parts
in the shaping machine,
being much lighter, en-
able us to adjust the


absorbing less
work by friction.

The machine in Plate
X. is by Messrs. Smith
& Coventry. The tool
box A is fixed to a 'ram'
B, the sliding of which in
saddle c gives the cut. The saddle moves along the bed r> to give
the feed, and an arm E, cast upon it, supports a rocking lever
F, which actuates the ram through the rod H. The cone
pulley rotates right-handed, carrying on its shaft (which
extends the whole length of bed) a pinion K, giving wheel L a
left-handed rotation. L turns on a stud fixed to the arm E, and
carries a crank pin P, whose throw may be adjusted similarly to
that in Plate XI. A die on this pin slides in a slot M, formed in
the oscillating lever F. Referring to Fig. 174^, the uniform
rotation of L will give the ram a slow advance when travelling from
a to , and a quick return from b to a, because -ab is a longer path
than ba, as shewn by the arrows; the proportion being 23 to 14